Do you need to file a Child Custody Affidavit? Learn how to process it and how to file for temporary custody from this article.This guide includes forms and instructions for a letter and affidavit to request that the court register an outofstate custody order in Texas. Everything you need to write a declaration letter to the judge in your custody case: an example, a downloadable template, an outline and tips. All child support forms are categorized and linked below as downloadable files. Select the category you need to see the corresponding forms. I understand I must fill out and attach a Declaration in Support of Changing. Primary Custody within One Year form to this Petition. Evidentiary materials must be submitted with this form to complete this section. Warning: The information and forms in this guide are not legal advice and are not a substitute for the help of a lawyer.